A heavyweight world title fight between Britain's Anthony Joshua and US rival Deontay Wilder has moved a step closer after promoter Eddie Hearn sat down with Wilder's management on Thursday to begin contract talks for a 2018 showdown.

WBA, IBF and IBO world champion Joshua and the WBC title-holder Wilder want the match-up as part of efforts to unify the heavyweight division.

Joshua has knocked out all 20 of his opponents to date, while Wilder has won all 39 of his professional fights and has been taken the distance only once.

But at the same time, Hearn wants to get Wilder in the ring with another of his fighters, Dillian Whyte, who is currently the WBC's number one ranked fighter after beating Robert Helenius last month in a World Boxing Council sanctioned eliminator.

Wilder will only agree to Whyte, as he's stated several times, if a showdown with Joshua is guaranteed in the contract.

"He's Eddie Hearn's dirty rag in his pocket or his spare tire on his car. He's a gatekeeper at best. If Dillian is the bridge to Joshua, make sure Joshua is at the end of that bridge," Wilder told BBC.

"All Eddie has to do is put AJ on that contract. I will only fight a peasant if the king is behind him."

Hearn claims Joshua wants the fight with Wilder, but it has to happen at the right time.

WBO champion Joseph Parker and a returning Tyson Fury are also being lined up as potential opponents for Joshua, who dominated Carlos Takam on his way to a 10th-round stoppage in Cardiff last month.

"Joshua has told me we want all the belts and that means taking on all the champions," added Hearn. "Tyson Fury, he's in the plans for 2018. Joseph Parker as well. Everybody wants to fight Anthony Joshua and you will see him fight everybody."